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argenx shares fell sharply on Thursday, October 8, after the biotechnology company said it would discontinue a Phase 3 trial of efgartigimod in adults with moderate-to-severe Sjögren’s disease. Investing.com reported that the stock was down 15.7% to €707.40 in Brussels trading after the announcement.
The company said an independent data monitoring committee recommended stopping the UNITY study for futility after an interim analysis found it was unlikely to meet its primary endpoint. The setback removes a late-stage opportunity to test efgartigimod in another autoimmune disease, though argenx also reported positive Phase 2 results for a separate drug candidate, FB102, in celiac disease.
Why the UNITY study is ending
UNITY was designed to assess whether weekly subcutaneous efgartigimod could reduce systemic disease activity in adults with moderate-to-severe Sjögren’s disease. The randomized, double-blind, placebo-controlled trial compared the drug with placebo, with change in disease activity at Week 48 set as its primary endpoint.
The monitoring committee’s futility recommendation means the study was judged unlikely to achieve that main measure. Argenx said safety was consistent with the established profile of efgartigimod, and that no new safety signals had been identified. The company did not release detailed efficacy results from the interim analysis in its announcement.
Argenx said it would close the study, lock the database and conduct a comprehensive analysis of the data. Chief Medical Officer Luc Truyen said the company was disappointed with the outcome and planned to share what it learned with the Sjögren’s community. The company has not announced a date for that analysis or any decision about further research in the disease.
A setback for a broader drug program
Efgartigimod is a central part of argenx’s immunology portfolio. The company describes it as a neonatal Fc receptor blocker that reduces circulating IgG antibodies. Its subcutaneous formulation, marketed as VYVGART Hytrulo, is approved for certain uses in generalized myasthenia gravis and chronic inflammatory demyelinating polyneuropathy; those existing indications are distinct from the Sjögren’s trial.
The UNITY study tested whether the medicine could extend into a disease characterized by immune-related damage to glands that produce tears and saliva, as well as possible systemic symptoms. Argenx said eligible participants had to meet classification criteria for primary Sjögren’s disease, test positive for anti-Ro/SSA antibodies and have moderate-to-severe systemic activity while on stable background care.
Investing.com’s same-day update also pointed to pressure in broader equity benchmarks. However, the company’s trial announcement supplies the specific corporate development coinciding with the share decline; the available reporting does not establish how much of the move was attributable to market-wide trading versus investors’ reassessment of the drug’s prospects.
Positive FB102 results offer a contrasting update
On the same day, argenx announced positive topline findings from a Phase 2 study of FB102 in adults with celiac disease. The company said the trial met its primary endpoint: change from baseline in the ratio of villus height to crypt depth at Day 78 compared with placebo, during a controlled gluten challenge. It reported a p-value of 0.0176.
The study enrolled 126 adults who had been following a strict gluten-free diet and assigned them to one of two FB102 dose groups or placebo while they underwent an eight-week oral gluten challenge. Argenx said additional measures, including intestinal immune-cell density and symptoms, were consistent with the primary result, and that no new safety signals were identified.
The company plans to advance FB102 into Phase 3 development, but detailed Phase 2 results are due to be presented at a future medical meeting. FB102 is a separate investigational medicine acquired through argenx’s August 2026 purchase of Forte Biosciences; its celiac results do not change the UNITY outcome. The company’s next stated steps for the Sjögren’s program are study close, database lock and further analysis, with no subsequent trial plan announced.
